Interesting website/Chrome-Firefox add-on: Builtwith.com
I ran across an interesting website this evening that goes into a website (you provide the URL) and digs out the underlying technologies that make up the site. Builtwith.com does this either via a web page where you enter the URL, or with a Chrome/Firefox add-on that adds a icon to your browser to do the same thing for the page you're currently on.
For instance, when I ran the add-on for the home page of my blog, it came back with a wealth of information:
I just installed the add-on to my Firefox browser this evening. Since it doesn't do anything until you click the icon, it shouldn't introduce any instability. If you don't want to clutter up your browser with add-ons, you can just go to their website to run the analysis.
This should be a great addition to a web designer's toolbox...